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M Paavola

Publications and source records attributed to M Paavola.

12 recordsLinked to original sources

[Pathophysiology of overuse tendon injury].

Overuse tendon injury is one of the most common injuries in sports. The etiology as well as the pathophysiological mechanisms leading to tendinopathy are of crucial medical importance. At the moment intrinsic and extrinsic factors are assumed as mechanisms of overuse tendon injury. Except for the acute, extrinsic trauma, the chronic overuse tendon injury is a multifactorial process. There are many other factors, such as local hypoxia, less of nutrition, impaired metabolism and local inflammatory that may also contribute to the development of tissue damage. The exact interaction of these factors cannot be explained entirely at the moment. Further studies will be necessary in order to get more information.

Achilles Tendon↗

Smoking cessation between teenage years and adulthood.

Most smokers begin smoking in adolescence. It is less well known how young people quit smoking and the factors that are associated with this process. A 15-year follow-up study on the North Karelia Youth Project has made it possible to assess these factors using a longitudinal study design. The project began in 1978 with students in Grade 7 of junior high school (age 13 years) and concluded in 1980 when the students reached Grade 9 (age 15 years). The follow-up study included four additional surveys. The present analyses are based on the data collected at ages 15, 21 and 28. The original sample comprised 903 students and the response rate of the last survey was 71%. A quarter (26%) of daily smokers and about half (46%) of occasional smokers at age of 15 had quit by the age of 28. The cessation rate was higher among females than males (P = 0.006). The cessation rate was higher among married (P = 0.015), employed (P = 0.01) and white-collar workers (P = 0.006). Cessation was less prevalent among those who had friends (P < 0.001) and family (P = 0.012) members who smoked. The cessation rate was lower among those who consumed fatty milk (P = 0.050), had less leisure-time physical activity (P = 0.032) and consumed more alcohol (P < 0.001). One-third of all teenage smokers stop smoking before the age of 28, averaging a 2.3% annual decline. Cessation is greater among occasional than daily smokers and greater overall among females.

Adolescent↗

Achilles tendon injuries.

The Achilles tendon is the strongest tendon in the human body. Because most Achilles tendon injuries take place in sports and there has been an common upsurge in sporting activities, the number and incidence of the Achilles tendon overuse injuries and complete ruptures have increased in the industrialized countries during the last decades. The most common clinical diagnosis of Achilles overuse injuries is tendinopathy, which is characterized by a combination of pain and swelling in the Achilles tendon accompanied by impaired ability to perform strenuous activities. Most patients with Achilles tendon injury respond favorably to conservative treatment and only those who fail to respond to carefully followed nonoperative treatment should undergo surgery for repair. A complete rupture of the Achilles tendon usually occurs in sports that require jumping, running, and quick turns. Although histopathologic studies have shown that ruptured Achilles tendons include clear degenerative changes before the rupture, many of the Achilles tendon ruptures occur suddenly without any preceding signs or symptoms. Neither conservative nor operative treatment is a treatment of choice for the ruptured Achilles tendon. It is generally accepted that surgery should be performed on ruptured Achilles tendons in young, physically active patients and in those patients for whom the diagnosis or the treatment of the rupture has been delayed, whereas the results of conservative treatment are an acceptable outcome in older patients with sedentary lifestyles. Many important issues still remain unanswered concerning the cause, pathogenesis, diagnosis, and management of the Achilles tendon disorders. Only when these issues have been solved by well-controlled studies can tailored treatment protocols be created.

Achilles Tendon↗

Magnetocardiographic QT interval dispersion in postmyocardial infarction patients with sustained ventricular tachycardia: validation of automated QT measurements.

QT dispersion is a measure of heterogeneity in ventricular repolarization. Increased ECG QT dispersion is associated with life-threatening ventricular arrhythmias. We studied if magnetocardiographic (MCG) measures of QT dispersion can separate postmyocardial infarction patients with and without susceptibility to sustained VT. Manual dispersion measurements were compared to a newly adapted automatic QT interval analysis method. Ten patients with a history of sustained VT (VT group) and eight patients without ventricular arrhythmias (Controls) were studied after a remote myocardial infarction. Single-channel MCGs were recorded from 42 locations over the frontal chest area and the signals were averaged. QT dispersion was defined as maximum-minimum or standard deviation of measured QT intervals. VT group showed significantly more QT and JT dispersion than Controls. QTapex dispersions were 127 +/- 26 versus 83 +/- 21 ms (P = 0.004) and QTend dispersions 130 +/- 37 versus 82 +/- 37 ms (P = 0.013), respectively. Automatic method gave comparable values. Their relative differences were 9% for QTapex and 27% for QTend dispersion on average. In conclusion, increased MCG QT interval dispersion seems to be associated with a susceptibility to VT in postmyocardial infarction patients. MCG mapping with automated QT interval analysis may provide a user independent method to detect nonhomogeneity in ventricular repolarization.

Algorithms↗

Fifteen-year follow-up of smoking prevention effects in the North Karelia youth project.

OBJECTIVES: This study evaluated the long-term effects of a school- and community-based smoking prevention program in Finland. METHODS: Four intervention schools from North Karelia and two control schools from another province were chosen for the evaluation. Students who received the intervention were taught to resist social pressures to smoke. The program began in 1978 with seventh-grade students and ran through 1980, with a 15-year follow-up. In North Karelia, a community-based smoking cessation program for adults was also carried out. RESULTS: Mean lifetime cigarette consumption was 22% lower among program subjects than among control subjects. Smoking and prevalence were lower up to the age of 21. CONCLUSIONS: Long-term smoking prevention effects can be achieved if a school-based program using a social influence model is combined with community and mass media interventions.

Adolescent↗

Ultrasonography in the differential diagnosis of Achilles tendon injuries and related disorders. A comparison between pre-operative ultrasonography and surgical findings.

PURPOSE: To assess the value of US in the diagnosis of various Achilles tendon disorders. MATERIAL AND METHODS: Pre-operative US was compared with surgical findings in 79 patients with an Achilles tendon complaint. RESULTS: US was highly reliable for verifying a complete Achilles tendon rupture, only one false-negative US examination was found in the 26 surgically verified cases. For diagnosing retrocalcanear bursitis, US was accurate: 6 out of the 8 cases of bursitis were found and there were no false-positive cases. There were also no false-positive US findings in patients with peritendinitis/tendinitis, but 7 false-negative US cases among the 40 surgically verified peritendinitis/tendinitis patients indicated that a negative US finding in a clinically suspected case of peritendinitis/tendinitis is unreliable. US also seemed to be inadequate for differentiating partial tendon rupture from a focal tendon degeneration. Nevertheless, the occurrence and location of such a lesion could be adequately determined by US. CONCLUSION: US can reliably be used for locating the Achilles tendon abnormality, estimating its severity, and determining most of the conditions requiring surgical intervention. However, US is not completely reliable for diagnosing peritendinitis and tendinitis, and it cannot be used to differentiate partial tendon ruptures from focal degenerative lesions.

Achilles Tendon↗

Stage-specific expression of pituitary adenylate cyclase-activating polypeptide (PACAP) mRNA in the rat seminiferous tubules.

We have used in situ hybridization and Northern blot analysis with oligonucleotide probe to characterize the site of pituitary adenylate cyclase-activating polypeptide (PACAP) synthesis in the rat testis. We observed strong hybridization signal in one third of the cross-sections of the seminiferous tubules, whereas some tubules were devoid of hybridization signal, thus suggesting that PACAP mRNA is expressed in a stage-specific manner. More detailed analysis showed that PACAP mRNA was present in round spermatids at stages III-VII of the cycle. Northern blot hybridization to RNAs extracted from samples of seminiferous tubules at different stages of the epithelial cycle confirmed that expression of PACAP mRNA is restricted to specific stages of the cycle. The highest amount of PACAP mRNA was detected at stages V to early -VII of the cycle, whereas very low levels of mRNA were present at stages I-II and IX-XIV. The present results demonstrate that PACAP mRNA is expressed in the developing germ cells. This suggests that PACAP may function as a paracrine or autocrine regulatory factor for the Sertoli and germ cells, with a specific function during early spermiogenesis, shortly before the onset of nuclear elongation, at the last period of haploid gene activity.

Animals↗

Seasonal variations in retinal detachment in Northern Finland and Novosibirsk.

Retinal detachments have a tendency to occur more commonly in spring and summer than in winter. Two new series are presented here, the first collected in Northern Finland at latitudes 64 degrees-70 degrees and the second from Novosibirsk, at a much lower latitude, 55 degrees N, but with an equally long winter. A statistically significant seasonal variation is found in both. The highest incidence peak is seen in June in Oulu and in July in Novosibirsk, the difference between the prevalence curves was, however, not statistically significant. The Oulu series shows a statistically highly significant seasonal variation in low refractive errors but no seasonal difference in high myopia and aphakia.

Climate↗

Bilateral acute retinal necrosis.

Four patients who experienced the sudden onset of anterior uveitis with large keratic precipitates and dense vitreous opacities developed confluent yellow-white swellings and exudates in the peripheral retina and sheathing and obliteration of retinal arteries. After absorption of the exudates, atrophic patches in the peripheral retina and a funnel-shaped retinal detachment with many tears appeared. Angiograms showed retinal edema, fluorescein leakage from the choroid in the affected areas, and perivasculitis of the retinal arteries. Although treatment seemed unable to alter the course of the disease, in one case the retina reattachment after vitrectomy and filling of the vitreous space with silicone oil. Histopathologic studies disclosed extensive atrophy and degeneration of the outer retinal layers and pigment epithelium and occlusion of the retinal vessels. An infection may trigger the uveitis, leading to an autoimmune sensitization against rods and cones that causes severe local immune-complex disease and retinal vasculitis.

Adult↗

Chronic Achilles tendon overuse injury: complications after surgical treatment. An analysis of 432 consecutive patients.

We analyzed the complications after surgical treatment of Achilles tendon overuse injuries in 432 consecutive patients. The patients underwent a clinical examination 2 weeks, and 1, 2, and 5 months after the surgery. If a complication appeared, the patient was followed up clinically for at least 1 year. There were 46 (11%) complications in the 432 patients: 14 skin edge necroses, 11 superficial wound infections, 5 seroma formations, 5 hematomas, 5 fibrotic reactions or scar formations, 4 sural nerve irritations, 1 new partial rupture, and 1 deep vein thrombosis. Fourteen patients with a complication had reoperations: four patients for skin edge necrosis, two for superficial wound infection, two for seroma formation, one for hematoma formation, two for fibrotic reaction or scar formation, two for sural nerve irritation, and one for a new partial rupture. About every 10th patient treated surgically for chronic Achilles tendon overuse injury suffered from a postoperative complication that clearly delayed recovery. However, the majority of patients with a complication healed and returned to their preinjury levels of activity. To reduce this morbidity, it is essential that the surgeon be continuously aware of the possibility of postoperative complications and use proper surgical techniques.

Achilles Tendon↗

Long-term prognosis of patients with achilles tendinopathy. An observational 8-year follow-up study.

To determine the long-term outcome of patients treated nonoperatively for acute or subchronic (duration of the symptoms before initiation of the treatment less than 6 months) Achilles tendinopathy, we performed a follow-up analysis on 83 of 107 patients an average 8 +/- 2 (SD) years after the initial contact. The analysis included a questionnaire, clinical examination, performance tests, muscle strength measurement, and ultrasonographic examination. Twenty-four of the 83 patients (29%) had to be operated on during the follow-up period. Seventy patients (84%) had full recovery of their activity level, and at 8 years' follow-up 78 patients (94%) were asymptomatic or had only mild pain with strenuous exercise. However, a clear side-to-side difference between the involved and the uninvolved sides was observed on the performance test, clinical examination, and ultrasonography. Also, 34 patients (41%) started to suffer from overuse symptoms in the initially uninvolved Achilles tendon. The results of our 8-year follow-up showed that the long-term prognosis of patients with acute-to-subchronic Achilles tendinopathy is favorable as determined by subjective and functional assessments. In the clinical and ultrasonographic examinations, mild-to-moderate changes were observed rather frequently in both the involved and initially uninvolved Achilles tendons, but the occurrence of these changes was not clearly related to the patients' symptoms.

Achilles Tendon↗